Vacuum sweeper



' April 14, 1936. c. o. BERGSTROM VACUUM SWEEPER Filed Feb. 26. 1955 M W 1a r $2 W E/A I J w IIII/IIIIIIIIII/IIIIlI/IIIII/IIIIIIIIIIIII Patented Apr. 14, 1936 UNITED STATES vnomm s'wnnraa Carl 0. Bergstrom, Boston, ma, alsignor to B. F. Sturtevant Company, Inc Hyde Park,

Boston, Mass.-

Application February 2c, 1935, Serial No. 8,290

4 Claims.

This invention relates to vacuum sweepers of the type employing rotary, sweeping brushes,-

, The ordinary electric motor which drives the action of the brushes is more a polishing action, than a sweeping one.

It is desirable that the rotary speed of the sweeping member of a vacuum sweeper be reduced substantially below that of the sweeping motor. A speed reduction such that the sweeping member revolves 'at about 800 revolutions per minute has been found satisfactory. Attempts to obtain this reduction in speed have been made in 25 the past, through the use of gear trains, planetary transmissions, etc., but the space available for this additional mechanism is so limited and the noise of, and. the power losses in, operation of such mechanisms have-prevented their successful operation.

According to this invention, the speed reducing mechanism for driving the sweeper brushes of a vacuum sweeper is confined within'a brush carrying cylinder of small diameter.

According to a feature of this invention, a pair of ball bearings is used to accomplish the desired speed reduction. A brush carrying cylinder is divided at its longitudinal center into two independent portions, eachcarrying a plurality of the usual sweeper brushes. A common shaft extends through both cylinders and attached to this shaft between the two cylinders is a pulley adapted to be rotated by a belt from another pulley carried by the shaft of the blower driving motor. ing through the two brush carrying cylinders is attached the inner race of a ball bearing. The outer races of these two ball bearings are held against rotation by the vacuum sweeper hous- 50 ing. The ball retaining ring in each bearing is attached to the outer end of its respective brush driven sweeping brushes as auxiliaries to vacuapproximating those of the motor armature, the

To each outer end of the shaft extend-' (Cl-1H) I pending primarily upon the size of the balls.

Since the ball'retaining rings are attached to the two brush carrying cylinders, it is seen that the cylinders are rotatedat the same reduced speed.

Since the speed reduction is accomplished through the use of a pair of simpleballs or other type of roller bearings, not only is ample space for their inclusion available but what is also important, the noise of operation is sllght'and the efficiency is high, all of these factors resulting in the production for the first time, of a small coinpact unit, which not only is efiective inits sweeping operation, but is inexpensive, quiet in operation and consumes but relatively little power.

An object of the invention is to drive a relatively low speed sweeper in a household vacuum sweeper from a relatively high speed bloiver motor, in quiet and eflicient operation.

Another object of the invention is to provide a quiet compact vacuum sweeper with revolving sweeper brush rotated at relatively low speed.

Another object of the invention is to drive a relatively low speed sweeper brush in a household vacuum sweeper, from a relatively high speed blower motor by driving the inner race of a ball or roller bearing by the motor, holding the outer race against rotation and attaching the sweeper brush to the ball or roller retaining ring of the bearing.

Other objects of-the invention will be apparent from the following description taken together with the drawing.

The invention will now be described with reference to the drawing, of which:

Fig, 1 is a partial view, partially in section, illustrating the sweeper brush driving mechanism of a household vacuum sweeper, according to this invention;

Fig. 2 is a sectional view, along the lines 2-2 of Fig. 1, and

Fig. 3 is a sectional view along the lines 33 I of Fig. 2. I

The two duplicate sweeper cylinders 4 are rotatably attached at their outer ends, by means of the clamping members 5 to the sweeper housing 6 and are so placed above the suction opening in the sweeper that when they are rotated, their brushes exert the desired sweeping action upon the surface being cleaned. The cylinders 4 are simultaneously rotated by the motor I which ordinarily drives the blower 8, by means of the belt 9 which extends over the pulley Ill-on the motor shaft and the pulley II. The pulley H is attached to the shaft I! which extends through a central opening in both cylinders 4.

At each end of the shaft I! are, fixedly attached, the hub member ii, on which is shrunk, forced or otherwise suitably attached, the inner race ll of a ball or roller bearing which revolves with the shaft l2. Between the balls I5 of the bearing, the pins l6 are attached at one end to the retaining ring IT. The other ends of the pins I6 are attached to the member I8, which in turn is attached to the outer race I! of a relatively small ball bearingmounted within each cylinder 4, and to the cylinder as by a forced or shrunk fit so that rotation of each retaining ring I! causes, through the intermediary of the pins l6 and member l8, rotation of the cylinder.

The inner race of the relatively small ball bearing, above mentioned, rests upon the shaft II, the purpose of this relatively small bearing being merely to support the outer end of its respective cylinder 4 upon, and to facilitate its rotation around, the shaft. 1

The outer race 20 of each relatively large hearing is held to prevent its rotation by pressure of the clamping members 5 against it. The clamping members 5 are attached to the housing 6 of the vacuum sweeper by means of the screws 2|. An inwardly extending portion 22 of each member 5 is, grooved to receive the felt 23, the outer portion" of which is pressed against the outer surface of each cylinder to prevent the entry of dust into the outer bearings,

The inner end of each .cylinder 4 is supported through the intermediary of the member 24 upon the outer race of a relatively small bearing indicat d-generally by 25 and the inner race of which ests upon the shaft II,- the purpose of this hearing being merely to support the inner end 0 the cylinder and to facilitate its rotation am I d the shaft l2-which as willibe explained later, rotates at a difierent speed.

With the armature of the motor I in rotation,

the belt 9 is driven by the pulley III to rotate the pulley II which in turn rotates the shaft H which extends through the two cylinders .4. The shaft in rotation rotates the hub member l3 and the inner ball race l4 due tothe fact that the outer ball race III is heldby the clamping member 5 to prevent its rotation. The retaining ring [1 rotates around the inner ball race l4 at a reduced speed. This. rotation of the retaining rings causes the rotation of the cylinders 4 through the intermediary of the pins l8 and members l8 in which the pins are held at one end. v

The cylinders 4 are rotated simultaneously in the same direction as described above and during rotation, the plurality of brushes 25 sweep the surface which is being cleaned.

The cylinders 4 rotate with little effort other.

is obtained through the use of the ball bearings,

Dower losses are very small and the noise of operation negligible. Then again, as pointed out above, it is poss ble to place the entire mechanism within a-vry small space as illustrated.

In the foregoing description, reference has been made to ball bearings. The invention, however, is not so limited since any equivalent form of bearings, such as cylindrical roller bearings, may be used. The term "roller bearings as used are rotated by said herein, is intended to include these and equivalent types.

Whereas, one embodiment of the invention has been described for the purpose of illustration, it

' should be understood that the invention is not 'limited to the exact arrangement described,

since many departures will suggest themselves to those skilled in; the art, after having had access to this disclo re,

What is claime is: s

1 .'In a vacuum cleaner, an agitator comprisinga 'cylinder having agitating elements on the periphery thereof, a rotatable shaft supporting said agitator, a motor, means for driving said shaft by said motor, a speed reducing mechanism of the roller bearing type having an inner race mounted on said shaft for rotation therewith, an outer race and a roller. retaining ring,

means for holding said outer race against rotation whereby on rotation of said inner race by said shaft, said ring is rotated at a reduced speed, and means connecting said ring and said cylinder whereby said cylinder is,rotated by said ring.

2. In a vacuum cleaner, an agitator comprising a cylinder having agitating elements on the periphery thereof, a rotatable shaft supporting said agitator, a motor, means for driving said shaft at one end of said cylinder by said motor, a speed reducing mechanism of the roller bearing type having an inner race mounted on said shaft at the other end of said cylinder for rotation there- 'with, an outer race and a roller retaining ring,

means for holding'said outer race against rotation whereby on rotation of said inner race by said shaft, said ring is rotated at a reduced speed, and means connecting said ring and said cylinder whereby said cylinder is rotated by said ring,

3. In a vacuum cleaner, an agitator comprisof the roller bearing type having an inner race for each cylinder mounted on said shaft for rotation therewith, an outer race and a roller retain-' ing ring for each cylinder, means for holding said outer races against rotation whereby on rotation of said inner races by said shaft,- said rings 'are rotated at a reduced speed, and means connecting each of said rings with its respective cylinder whereby said cylinders are rotated by said rings.

4. In a. vacuum cleaner, an'a'gitator comprising tion whereby upon rotation of said inner races 

